Thompson, UT frost dates
How Thompson compares
- In 8 years out of 10, the last spring frost in Thompson falls between April 7 and May 8, a 31-day window. The first fall frost falls between October 6 and November 1.
- The median last frost is 18 days earlier than the Utah median of May 10.
- Its 181-day growing season is longer than 80% of the 250 Utah places with a regular frost season (state median 148 days).
- The last frost is typical for zone 6b, where the median is Apr 22.
- The weather station records an average of 138 nights a year at or below 32°F.
- Compared with Grand Junction, CO, 103 km away, the last frost here is 1 day earlier than there and the growing season is 1 day longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 7 |
| 50% (median) | April 22 |
| 10% (safe for tender plants) | May 8 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 6 |
| 50% (median) | October 20 |
| 90% (late) | November 1 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Thompson, UT
Thompson, UT frost dates — last frost Apr 22, first frost Oct 20, zone 6b. whenisthelastfrost.com
When to plant vegetables in Thompson, UT
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 28 – Feb 11 | Mar 25 – Apr 8 | — | — |
| Peppers | Feb 11 – Feb 25 | May 6 – May 20 | — | — |
| Eggplant | Feb 11 – Feb 25 | May 6 – May 20 | — | — |
| Tomatoes | Feb 25 – Mar 11 | Apr 29 – May 13 | — | — |
| Lettuce | Feb 25 – Mar 11 | Apr 1 – Apr 15 | Mar 25 – Apr 29 | Aug 25 – Sep 22 |
| Kale | Feb 25 – Mar 11 | Mar 25 – Apr 8 | Mar 25 – Apr 8 | Aug 11 – Sep 1 |
| Broccoli | Feb 25 – Mar 11 | Apr 8 – Apr 22 | — | Jul 14 – Aug 4 |
| Cabbage | Feb 25 – Mar 11 | Apr 1 – Apr 15 | — | Jul 14 – Aug 4 |
| Cauliflower | Feb 25 – Mar 11 | Apr 8 – Apr 22 | — | Jul 14 – Aug 4 |
| Okra | Mar 11 – Mar 25 | May 13 – May 27 | May 13 – May 27 | — |
| Basil | Mar 11 – Mar 25 | Apr 29 – May 13 | — | — |
| Peas | — | — | Mar 11 – Apr 1 | Jul 28 – Aug 18 |
| Spinach | — | — | Mar 11 – Apr 1 | Aug 25 – Sep 15 |
| Radishes | — | — | Mar 18 – Apr 29 | Sep 8 – Sep 29 |
| Cucumbers | Mar 25 – Apr 1 | May 6 – May 13 | Apr 29 – May 13 | Aug 4 – Aug 18 |
| Zucchini & Summer Squash | Mar 25 – Apr 1 | — | Apr 29 – May 13 | Aug 11 – Aug 25 |
| Winter Squash & Pumpkins | Mar 25 – Apr 1 | — | Apr 29 – May 13 | — |
| Melons & Watermelon | Mar 25 – Apr 1 | May 6 – May 20 | — | — |
| Carrots | — | — | Apr 1 – Apr 29 | Jul 28 – Aug 11 |
| Beets | — | — | Apr 1 – Apr 29 | Aug 11 – Aug 25 |
| Potatoes | — | — | Apr 1 – Apr 22 | — |
| Swiss Chard | — | — | Apr 8 – May 6 | Aug 11 – Aug 25 |
| Cilantro | — | — | Apr 8 – Apr 29 | Aug 25 – Sep 15 |
| Green Beans | — | — | Apr 29 – May 20 | Aug 4 – Aug 18 |
| Sweet Corn | — | — | Apr 29 – May 13 | — |
| Sweet Potatoes | — | May 6 – May 27 | — | — |
| Garlic | — | — | — | Oct 6 – Nov 10 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Moab Canyonland Ap, UT weather station, 24 km away (elevation 4,560 ft (1,390 m)).
Frost dates near Thompson
- Cisco Apr 27 · Oct 9
- Green River Apr 22 · Oct 20
- Moab Apr 11 · Oct 23
- La Sal May 17 · Oct 6
- Sunnyside Apr 26 · Oct 25
- East Carbon Apr 26 · Oct 25
- Elmo May 27 · Sep 26
- Cleveland May 18 · Sep 27
- Wellington May 27 · Sep 26
- Huntington May 18 · Sep 27
Frequently asked questions
When is the last frost in Thompson, UT?
The median last spring frost in Thompson, UT is April 22. There is still about a 10% chance of frost after May 8, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Thompson, UT?
The median first fall frost is October 20, with about a 10% chance of frost before October 6.
How long is the growing season in Thompson, UT?
About 181 days between the median last spring frost and first fall frost.
What planting zone is Thompson, UT?
Thompson, UT is in USDA hardiness zone 6b.